Powered metal spinning apparatus



6. H. iKERT POWERED METAL SPINNING APPARATUS Aug 1, 1967 2 Sheets-Sheet1 Filed June 20, 1961 1, 1967 G. H. iKERT 3,333,448

POWERED METAL SPINNING APPARATUS Filed June 20, 1961 2 Sheets-Sheet 2 J1/5 110 701 J06 23 o J 512 INVENTOR,

J05 J10 6205 96 Zlfwr' United States Patent POWERED METAL SPINNINGAPPARATUS George H. Ikert, Elgin, 11]., assignor to Calumet & Hecla,

Inc., Chicago, Ill., a corporation of Michigan Filed June 20, 1961, Ser.No. 118,342 The portion of the term of the patent subsequent to June 13,1981, has been disclaimed 6 Claims. (CI. 72-85) This invention relatesgenerally to methods of formmg metals and especially to metal spinning.

Metal spinning has been practiced for centuries, and the utility of thismetal forming process is attested to by the extent to which it isemployed, essentially unchanged, even in our modern age of automation.Metal spinning is generally considered to be an art or craft exactingmanual skill, judgment, physical strength and endurance considerablybeyond that required of an operator in other metal forming processes.Reduced to its rudiments, metal spinning entails the pressing of a toolagainst the side of a spinning metal blank according to a deliberatesequence until the originally flat blank is completely formed against avolumetric chuck. Since the wall thickness of the blank can be eitherincreased or decreased during spinning, the operator must retain tactilecontact with the forming metal in order to control the wall thickness ofthe finished part. As the original thickness and temper of the metalblank is increased, so also are the physical demands on the operator,especially if he is to maintain his feel of the forming metal. Compoundspinning apparatus has .been developed, employi ng a lever arrangementfor multiplying the operators physical efforts; however, even thisapparatus imposes appreciable demands on the operators strength andendurance during an ordinary work shift.

Accordingly, an important object of the present invention is to providemetal spinning apparatus incorporatmg power assistance for movement ofthe spinning tool and ensuring tactile perception of the forming of theworkpiece.

A more general object of the invention is to provide new and improvedmetal spinning apparatus.

Another object of the invention is to provide metal spinning apparatusthat places but small physical demands on the operator.

Yet another object of the invention is to provide powered metal spinningapparatus that uses the normal spinning skills and techniques.

Additional objects and features of the invention pertain to theparticular structure and arrangements where- ,by the above objects areattained.

Spinning apparatus in accord with the invention includes a tool rest, afulcrum lever pivotally mounted on the tool rest, a spinning leverpivotally mounted on the fulcrum lever and carrying a spinning toolthereon, hydraulic acks acting between the levers and the tool rest,control valves for the hydraulic jacks functioning in response toactuating forces in excess of a predetermined value, and handle elementspivotally mounted respectively on the fulcrum lever and on the spnninglever adapted for pivoting the respective lever upon application ofmanual force less than the predetermined value and for actuating thecorresponding control valve upon application of manual force more thanthe predetermined value.

The invention, both to its structure and mode of operation, will bebetter understood by reference to the following disclosure and drawingsforming a part thereof, wherein:

FIG. 1 is a perspective view of powered metal spinning apparatusconstructed in accordance with the invention;

3,333,448 Patented Aug. 1, 1967 FIG. 2 is a schematic plan view of thelevers and hydraulic arrangements used in the apparatus of FIG. 1;

FIG. 3 is a schematic view of the spinning lever, the associatedhydraulic jack and the control valve for the jack, the valve spool inthe control valve being shown in the neutral position in which noactuation of the jack piston is realized;

FIG. 4 is a view similar to the showing of FIG. 3 with the several partsrearranged for powered movement of the lever to the right as viewed inthe drawing; and

FIG. 5 is a view similar to the showing of FIG. 3 but with the partsrearranged for powered movement of the lever to the left as viewed inthe drawing.

Referring now in detail to the drawings, particularly to FIGS. 1 and 2,a powered metal spinning apparatus will be seen to comprise a lathemachine 10 including a rotatable drive head 12 receiving motive forcefrom. an electric motor 14. A volumetric chuck 16 is mounted to thedrive head 12, and a metal blank 18 is held securely against the chuck16 by means of a tail block 20. A tool rest arrangement shown generallyat 22 is fixed to the lathe machine 10 spaced laterally apart from andparallel to the common axis of head 12, chuck 16 and tail block 20. Thetool rest arrangement 22 includes an elongated member 24 havinglaterally formed extensions 26 and 28 rigidly fastened at its end. i

A dog-leg-shaped, compound or fulcrum lever 30 is pivotally mounted tothe member 24 intermediate its ends. Advantageously, the compound lever30 overlies the member 24 and is pivotally connected thereto by means ofa pin 32 entering aligned bores in the lever 30 and the member 24. Aswill be recognized, pin 32 may be prevented-from axial movement relativeto the lever 30 by heading, by provision of a collar, or other suitablemeans. In addition, the drilling of a series of holes in the member 24permits considerable adjustment in the position of the compound leverrelative to the workpiece.

A roll or spining lever 34 is pivotally mounted on the offset endportion of the compound lever 30 by means of a pin 36 entering alignedbores in the respective levers. As will be recognized, certain variationin the leverage applied by the interaction of the levers can be achievedby repositioning the spinning lever 34 along the offset end portion oflever 30. The lever 34 carries a spinning tool 38 on which is nearestthe workpiece; and while a wheel-like tool has been illustrated, anytype of spinning tool may be used.

In accordance with an important feature of the invention, an arrangementof hydraulic cylinders and valves is provided for supplementing anoperators manual manipulation of the levers 30 and 34. Specifically, adouble-acting hydraulic jack 40 operates between the spinning lever 34and the extension 28 of the tool rest. Similarly, a double-actinghydraulic jack 42 operates between the compound lever 30 and theextension 26.

As is particularly well shown in FIG. 2, the hydraulic jack 40 includesa cylinder 44 that is swingably mounted to the lever 34 by means of anarm 46 and a pivot st-ud 48. The jack 40 also includes a piston 50having a piston rod 52 fixed thereto. At the end of rod 52 away from thepiston 50, a coupling 54 swingably mounts the jack 40 to the extension28. In similar manner, the jack 42 includes a cylinder 56 which isswingably mounted to lever 30 by means of an arm 58 and a pivot stud 60,the jack 42 also including a piston 62 and a piston rod 64. The pistonrod 64 is appropriately swingably mounted to the extension 26 by meansof a coupling 66.

Hydraudic fluid is supplied to the jacks 40 and 42 from a pump 68, pump68 withdrawing fluid from a reservoir 70 that is associated with thereturn hydraulic lines.

The operation of each of the hydraulic jacks 40 and 42 is regulated anddirected by a control valve arrangement, control valve arrangements 72and 74 respectively. These hydraulic control valves are actuated byhandles 76 and 78 respectively, the handle 76 being pivotally mounted tothe spinning lever 34 at 80 and being connected to the operating memberof valve 72 by the ball stud 82. Handle 78 is pivotally connected to thecompound lever 30 at 84 and is arranged to actuate the operating memberof valve 74 through a ball stud 86.

Detailed descriptions of the construction of control valve 72, of thehydraulic connections between valve 72 and jack 40, and of the operationof these elements will now be given with reference to FIGS. 3-5.

The control valve 72 will be seen to comprise a valve body or housing 90that is provided with a threaded bore 93 opening from one end. AnL-shaped arm 94 is welded or otherwise rigidly fastened to an extension96 of spinning lever 34; and the free end of arm 94 is appropriatelythreaded for progressive engagement with the threaded bore 92 andresultant rigid attachment of the valve body 90 to the spinning lever34.

The valve body 90 is fashioned with a central bore 98 in which a valvespool 100 reciprocably operates. The valve body also defines a pair ofpassageways 102 and 104 communicating with a common conduit 105 whichleads to the pump 68. The valve body 90 also defines a pair ofpassageways 106 and 108 situated approximately diametrically to butoffset slightly from the passageways 102 and 104, passageways 106 and108 communicating respectively with the jack cylinder 44 on oppositesides of the piston 50. Passageways 106 and 108 specifically communicatewith the cylinder 44 through conduits 110 and 112 respectively. Thevalve body 90 is further fashioned with a radial cavity 114 opening intothe bore 98 intermediate the passageways 106 and 108. A passageway 116opens into bore 98 diametrically from cavity 114 and is connected toreservoir 70 by a conduit 118.

The spool 100 includes a central shaft 120 and three annular, radiallyextending, flange-like valve members, valve members 122, 124 and 126.Valve member 122 is adapted for selective opening and closing of thepassageways 102 and 106; the valve member 124 is arranged for selectiveopening a closing of the passageway 116 and the cavity 114; and thevalve member 126 is arranged for selective opening and closing of thepassageways 104 and 108. The valve spool 100 is centered in the bore 98by means of a compression spring 128, two rigid retainer washers,washers 130 and 132, and spaced apart, annular shoulders formed in thevalve body 90 for individual cooperation with the Washers 130 and 132.

The ball nut 82 is connected to the shaft 120 of valve spool 100 so thatmanually applied forces on the handle 76 tending to rotate the handleabout the pivot 80 will be transmitted to the valve spool for relocationof the valve members 122, 124 and 126. The spring 128 is advantageouslyselected to balance forces of approximately four pounds so that onlyforces in excess of that value are capable of relocating the valve spool100. Thus, manual forces tending to rotate the handle 76 about the pivot80 which do not exceed four pounds in total pressure do not operate thevalve 72 but are transmitted directly to the spinning lever 34 forarcuate movement thereof about the pivot pin 36, fluid being transferredfrom one side of piston 50 to the other through cavity 114 to permitthis movement. When such manual forces do exceed the value necessary toovercome the spring 128, the valve spool is relocated to result in jack40 providing power assistance to the desired movement of the lever 34.

' The neutral position of valve 72 in which there is no actuation ofjack piston 50 is shown in FIG. 3. There, it will be observed, the valvemember 124 is in blocking relationship relative to the passageway 116preventing any return of hydraulic fluid to the reservoir 70. Inaddition, the valve member 122 is positioned opening both the pas- 4sageways 102 and 106. Similarly, the valve member 126 is disposedopening the passageways 104 and 108. Thus,

hydraulic fluid from the pump 68 is transmitted to both sides of thepiston 50 for balancing the piston and avoiding movement thereof.

Because of the pivotal arrangement of spinning lever 34, desiredmovement of the lever in the direction indicated in FIG. 4 by arrow 134is realized by urging the handle 76 in the direction indicated by arrow136. When the force imposed upon the handle in the direction of arrow136 exceeds the spring pressure of spring 128, the valve spool moves tothe right as shown in FIG. 4. As a result of this movement, the valvemember 122 blocks the passageway 102 and the valve member 124 opens thepassageway 116 to the return line to the reservoir 70. As the conduit isthus evacuated, the fluid pressure from pump 68 passing through thepassageways 104 and 108 and into the conduit 112 urges the piston 50 inthe direction of arrow 138 providing power assistance for the desiredmovement of the lever 34.

FIG. 5 shows the arrangement of valve 72 for power assistance inmovement of the lever 34 in the direction indicated by arrow 140. Uponmovement of the handle 76 in the direction indicated by arrow 142 withsuch force as to overcome the spring 128, the valve spool 100 isresituated as shown. Valve member 126 opens passageway 108 tocommunication with passageway 116 around the lands of valve member 124,valve member 126 simultaneously closing off passageway 104. In addition,valve member 122 is positioned in non-obstructing relationship relativeto the pasageways 102 and 106. Thus, return flow of hydraulic fluid fromthe right side of piston 50 through the conduit 112 and to the reservoir70 is incurred; and the fluid pressure from pump 68 is transmittedthrough the passageways 102 and 106 and through the conduit 110 to theleft hand side of the piston 50 as viewed in FIG. 5. As a result, thepiston will be displaced in the direction of arrow 144 to provide powerassistance to the movement of lever 34 in the direction of arrow 140.

As will be recognized, any time in the course of the manipulation oflever 34 that the force imposed on the handle 76 falls below thatnecessary to overcome the spring 128, the spring will center the spool100 in the neutral position illustrated in FIG. 3 whereupon manualcontrol of the lever will be realized. On the other hand, when themanual forces imposed upon handle 76 exceed the spring pressure ineither direction, force from the hydraulic jack 40 will be developedcausing the desired movement of the spinning lever.

Control valve 74 is constructed and oriented similarly to control valve72; and since jack 42 is arranged oppositely to jack 44 in accordancewith the showing of FIG. 2, it will be apparent that valve 74 operatesjack 42 in a manner reverse of that described immediately hereinabovefor valve 72 and jack 40.

Operation of the metal spinning apparatus of the invention will beapparent from the foregoing descriptions.

It is to be recognized that the machine operator is able to maintaintactile contact with the spinning metal blank since conscious effort isnecessary on his part to move the levers 30 and 34 so as to cause thespinning tool to follow the yielding metal blank. In accordance with theinvention, power assistance is available, but movement of the toollevers must be initiated by manual force outside of the hydraulic powersystem.

The specific embodiment of the invention herein shown and describedshould be considered as illustrative only. Various changes in structurewill, no doubt, occur to those skilled in the art; and such changes areto be understood as forming a part of this invention insofar as theyfall within the spirit and scope of the appended claims.

The invention is claimed a follows:

1. Metal spinning apparatus comprising: tool rest means; a fulcrum leverpivotally mounted on said tool rest means; first hydraulic jack meansacting between said lever and said tool rest means; control valve meansfor said jack means functioning in response to actuating forces inexcess of a predetermined value; handle means on said fulcrum leveradapted for pivoting said lever upon application of manual forces lessthan said predetermined value and for actuating said control valve meansupon application of manual forces at least equal to said predeterminedvalue; a roll lever pivotally mounted on said fulcrum lever and carryinga spinning tool thereon; second hydraulic jack means acting between saidroll lever and said tool rest means; control valve means for said secondjack means functioning in response to actuating forces in excess of apredetermined value; and handle means on said roll lever adapted forpivoting said lever upon application of manual forces less than saidpredetermined value and for actuating said control valve means uponapplication of manual forces at least equal to said predetermined value.

2. Metal spinning apparatus according to claim 1 wherein each of saidcontrol valve means includes a plurality of flow passagewayscommunicating with the cylinder of the cooperating jack means, a valvespool selectively opening and closing said passageways and a centeringspring operative to position said spool normally in a neutral positionassociated with inaction of said jack means.

3. Metal spinning apparatus according to claim 1 wherein saidpredetermined force value is approximately four pounds.

4. Metal spinning apparatus comprising: tool rest means having laterallyformed, oppositely disposed terminal extensions; a fulcrum leverpivotally mounted on said tool rest means; first double acting hydraulicjack means acting between said lever and one of said terminalextensions; control valve means for said jack means functioning inresponse to actuating forces in excess of a predetermined value; handlemeans pivotally mounted on said fulcrum lever adapted for pivoting saidlever upon application of manual forces less than said predeterminedvalue and for actuating said control valve means upon application ofmanual forces greater than said predetermined value; a roll leverpivotally mounted on said fulcrum lever and carrying a spinning toolthereon; second double acting hydraulic jack means acting between saidroll lever and the other of said terminal extensions; control valvemeans for said second jack means functioning in response to actuatingforces in excess of a predetermined value; and handle means pivotallymounted on said roll lever adapted for pivoting said lever uponapplication of manual forces less than said predetermined value and foractuating said control valve means upon application of manual forcesgreater than said predetermined value.

5. Metal spinning apparatus according to claim 4 wherein each of saidcontrol valve means includes two flow passageways connected to thecylinder of the cooperating jack means respectively on opposite sides ofthe piston thereof, a valve spool selectively opening and closing saidpassageways, and a centering spring operative to position said spoolnormally opening both of said passsageways.

6. Metal spinning apparatus according to claim 4 wherein saidpredetermined force value is approximately four pounds.

References Cited UNITED STATES PATENTS 603,096 4/1898 Worth l13522,918,850 12/ 1959 Swanson et a1. -13.5 3,053,234 9/1962 Chevreux 121-41OTHER REFERENCES Product Engineering, Jan. 5, 1959, pp 42-47.

RICHARD J. HERBST, Primary Examiner.

NEDWIN BERGER, Examiner.

K. A. COCKS, Assistant Examiner.

1. METAL SPINNING APPARATUS COMPRISING: TOOL REST MEANS; A FULCRUM LEVERPIVOTALLY MOUNTED ON SAID TOOL REST MEANS; FIRST HYDRAULIC JACK MEANSACTING BETWEEN SAID LEVER AND SAID TOOL REST MEANS; CONTROL VALVE MEANSFOR SAID JACK MEANS FUNCTIONING IN RESPONSE TO ACTUATING FORCES INEXCESS OF A PREDETERMINED VALUE; HANDLE MEANS ON SAID FULCRUM LEVERADAPTED FOR PIVOTING SAID LEVER UPON APPLICATION OF MANUAL FORCES LESSTHAN SAID PREDETERMINED VALUE AND FOR ACTUATING SAID CONTROL VALVE MEANSUPON APPLICATION OF MANUAL FORCES AT LEAST EQUAL TO SAID PREDETERMINEDVALUE: A ROLL LEVER PIVOTALLY MOUNTED ON SAID FULCRUM LEVER AND CARRYINGA SPINNING TOOL THEREON; SECOND HYDRAULIC JACK MEANS ACTING BETWEEN SAIDROLL LEVER AND SAID TOOL REST MEANS; CONTROL VALVE MEANS FOR SAID SECONDJACK MEANS FUNCTIONING IN RESPONSE TO ACTUATING FORCES IN EXCESS OF APREDETERMINED VALUE; AND HANDLE MEANS ON SAID ROLL LEVER ADAPTED FORPIVOTING SAID LEVER UPON APPLICATION OF MANUAL FORCES LESS THAN SAIDPREDETERMINED VALUE AND FOR ACTUATING SAID CONTROL VALVE MEANS UPONAPPLICATION OF MANUAL FORCES AT LEAST EQUAL TO SAID PREDETERMINED VALUE.